Remove deprecated Import model

[mjankowski]

Attempting to remove the deprecated code from #21054

[renchap]

This needs to be merged before we release our next major update, as it will prevent to update from a pre-4.2 version to the version containing this.

[ClearlyClaire]

This needs to be merged before we release our next major update, as it will prevent to update from a pre-4.2 version to the version containing this.

You meant “after we release our next major update”?

[renchap]

No, before we release it? So people can upgrade to the latest 4.x release (and we know they will have done the migration) then upgrade to 5.0 (which will require you to be up-to-date on the latest 4.x before upgrading to the next major)

[ClearlyClaire]

Ok, I think we do agree, I just was confused by your initial post as it seemed to imply the earlier it was merged, the better.

The cost of merging it early is breaking in-progress imports for instances updating from pre-4.2.0 to a release containing this change.

The cost of merging it late is carrying “dead” code for longer.

I agree that 5.0 sounds like a good breakpoint to get rid of this.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has resolved merge conflicts and is ready for review.